Tonight's TV picks: 'Blue Bloods' ready for season finale cliffhanger

Nick and Hank (David Giuntoli, Russell Hornsby) investigate a double homicide that's linked to the Verrat. Meanwhile, Trubel (Jacqueline Toboni) meets a father-and-son team who traveled a great distance to find "the Portland Grimm," and Renard (Sasha Roiz) grows suspicious of Adalind's behavior.

"Blue Bloods" (10 p.m., CBS): We smell a great big juicy cliffhanger in the season finale. Danny (Donnie Wahlberg) disobeys orders and investigates a case he was told was off-limits. The "shocking" information he uncovers could have serious repercussions within the department.